The best portrayal of Eliza that I've ever seen came in a Los Angeles production of Pygmalion with Robert Stephens and Roberta Maxwell. Her Eliza was tough as nails. Her essence didn't change by the end, only her manners and speech. When she said "she shouldn't mind a black eye" you felt she would give one back. She was ready to fight! It was a most unsentimental version and, I think, close to what Shaw intended.